Advertisement

The Pliocene Shelburne Mass-Movement and Consequent Tsunami, Western Scotian Slope

  • D. C. MosherEmail author
  • Z. Xu
  • J. Shimeld
Chapter
Part of the Advances in Natural and Technological Hazards Research book series (NTHR, volume 28)

Abstract

Submarine mass-movement is a significant process along continental margins, even along passive margin slopes. Interpretation of seismic reflection profiles along the Scotian margin, for example, indicates the Cenozoic section is dominated by mass transport deposits (MTD) at a spectrum of scales. Occasional exceptionally large MTDs are observed which seem particularly foreign in a passive continental margin setting. The Shelburne MTD was recognized from exploration industry seismic reflection data along the western Scotian Slope. It is a buried Plio/ Pleistocene feature that extends in excess of 100 km from the upper slope to the abyssal plain and maps to an area in excess of 5,990 km2 and a volume >862 km3. Its features demonstrate that it is a frontally-emergent MTD with a slump portion and a debris flow/run-out portion. Tsunami simulations were generated for this event, one assuming the slump portion generated the tsunami, the other, both the slump and debris flow contributed. For a mass movement comparable in scale to the Shelburne MTD, these simulations demonstrate that the city of Halifax, Nova Scotia, would be impacted within 70 to 80 minutes by a 13–25 m high wave, depending on the MTD source volume (slump or slump and debris field).

Keywords

Submarine landslide mass-failure mass-transport deposit tsunami geohazard seismic reflection 

Notes

Acknowledgments

The authors would like to express their appreciation to TGS-Nopec for permitting use of the seismic data and to D.C. Campbell and S. Bartel for assistance with interpretation and technical issues. This work was conducted under the NRCan Geoscience for Ocean Management Program. We also thank the reviewers Drs. K. Moran and A. Zakeri for critiquing and improving this manuscript.

References

  1. Bondevik S, Lovholt F, Harbitz C, Mangerud J, Dawson A, Scendsen JI (2005) The Storegga slide tsunami—comparing field observations with numerical simulations. Mar Pet Geol 22: 195–208.CrossRefGoogle Scholar
  2. Campbell DC and Mosher DC (this volume) Middle Cenozoic unconformities and slope failure on the western Scotian margin. In: Mosher DC et al (eds) Submarine Mass Movements and Their Consequences I V. Springer, The Netherlands.Google Scholar
  3. Clague JJ, Munro A, Murty TS (2003) Tsunami hazard and risk in Canada. Nat Hazards 28: 433–461.CrossRefGoogle Scholar
  4. Doxsee WW (1948) The grand banks earthquake of November 18, 1929. Publ Dom Obs 7.Google Scholar
  5. Frey-Martinez J, Cartwright J, James D (2006) Frontally confined versus frontally emergent submarine landslides: a 3D seismic characterization. Mar Petrol Geol 23: 585–604.CrossRefGoogle Scholar
  6. Grilli ST, Watts P (2005) Tsunami generation by submarine mass failure: modeling, experimental validation, and sensitivity analyses. J Waterw Port C 131: 283–297.CrossRefGoogle Scholar
  7. Haflidason H, Lien R, Sejrup HP, Forsberg CF, Bryn P (2005) The dating and morphemetry of the Storegga Slide. Mar Petrol Geol 22: 123–136.CrossRefGoogle Scholar
  8. Harbitz CB, Løvholt F, Pedersen G, Masson DG (2006) Mechanisms of tsunami generation by submarine landslides: a short review. Nor J Geol 86: 255–264.Google Scholar
  9. Heaps NS (1969) A two-dimensional numerical sea model. Philos Trans R Soc Lon A, Math Phys Sci, 265: 93–137.CrossRefGoogle Scholar
  10. LeBlanc C, Louden K, Mosher DC (2007) Gas hydrates on the Nova Scotia Slope: velocity models from wide-angle seismic profiles. Mar Petrol Geol 24: 321–334.CrossRefGoogle Scholar
  11. Lovholt F, Harbitz CB, Haugen KB (2005) A parametric study of tsunamis generated by submarine slides in the Ormen Lange/Storegga area off western Norway. Mar Petrol Geol 22: 219–231.CrossRefGoogle Scholar
  12. Mason D, Harbitz C, Wynn R, Pederson G, Lovholt F (2006) Submarine landslides: processes, triggers and hazard protection. Philos Trans R Soc 364: 2009–2039.CrossRefGoogle Scholar
  13. Mazzotti S (2007) Geodynamic models for earthquake studies in intraplate North America. In: Stein S, Mazzotti S (eds) Continental Intraplate Earthquakes Science, Hazard, and Policy Issues. Geol Soc Am Spec Pap 425: 17–33.Google Scholar
  14. McCall C, Morrison ML, Piper DJW, (2005) Geological data from the St. Pierre Slope around the epicentre of the 1929 Grand Banks earthquake. Geol Surv Can Open File: 4879.Google Scholar
  15. Mosher DC, Moran KM and Hiscott RN (1994) Late Quaternary sediment, sediment mass-flow processes and slope instability on the Scotian Slope. Sedimentol 41: 1039–1061.CrossRefGoogle Scholar
  16. Mosher DC, Piper DJW (2007) Analysis of multibeam seafloor imagery of the Laurentian Fan and the 1929 Grand Banks landslide area. In: Lykousis V, Dimitris S, Locat J (eds) Submarine Mass Movements and Their Consequences, III. Springer, The Netherlands, 77–88.CrossRefGoogle Scholar
  17. Mosher DC, Piper DJW, Campbell DC, Jenner KA (2004) Near surface geology and sediment failure geohazards of the central Scotian Slope. Am Assoc Petrol Geol Bull 88: 703–723.Google Scholar
  18. Piper DJW, Aksu AE (1987) The Source and origin of the 1929 Grand Banks turbidity current inferred from sediment budgets. Geo-Mar Lett 7: 177–182.CrossRefGoogle Scholar
  19. Ruffman A (1997) Tsunami runup mapping as an emergency preparedness planning tool: the 1929 tsunami in St. Lawrence, Newfoundland. Geomarine Associates, Contract Report for Emergency Preparedness Canada (EPC), Ottawa, Ontario 1: 107 pp.Google Scholar
  20. Shimeld JW, Warren SN, Mosher DC, MacRae RA (2003) Tertiary-aged megaslumps under the Scotian Slope, south of the LaHave Platform, offshore Nova Scotia. In: Joint Meet, Program with Abstr, Geol Soc Am (NE Sect) and the Atl Geosci Soc, Halifax, Nova Scotia.Google Scholar
  21. Wade JA, MacLean BC (1990) Aspects of the geology of the Scotian Basin from recent seismic and well data. In: Keen MJ, Williams GL (eds) Geology of the continental margin off eastern Canada. Geol Surv Can, Geology of Canada, No. 2 (also Geol Soc Am, The Geology of North America, I-1: 190–2380).Google Scholar
  22. Xu Z (2007) The all-source Green's function and its applications to tsunami problems. Sci Tsunami Hazards 26: 59–69.Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Geological Survey of Canada, Natural Resources Canada BedfordInstitute of OceanographyCanada
  2. 2.Canadian Hydrographic Service, Fisheries and Oceans CanadaMaurice-LaMontagne LaboratoryMont-JoliCanada

Personalised recommendations